Golf has become a popular recreational game. In the game of golf a ball is played from the teeing ground to the putting green by successive strokes, and once on the putting green into the hole, using a specialised club called a putter.
A conventional short putter (FIG. 1) is between 85 and 90 cm. in total length, and has a single grip 1, located at a top end of a shaft 2, and a putter head 3 located at a bottom end of the shaft. The player grasps the single grip with both hands (FIG. 2) when putting the ball with the putter head 3.
Whilst the use of a putter is an apparently simple action, it is perhaps the part of golf which is least reliable from day to day. A common problem that golfers experience when putting is excessive wrist flexure, or hinging of the wrists, when swinging their putter, which contributes to inconsistency of both direction and distance control.
An extreme form of poor putting is a condition known as the “yips”, whereby the golfer has greatly excessive wrist flexure in his/her stroke, sometimes accompanied by excessive body movement as well. It has been known for golfers suffering from the putting “yips” to occasionally even miss the ball completely.
Many famous golfers, including Sam Snead, Ben Hogan, Bernhard Langer, and Tom Watson have had periods of very unreliable short distance putting, using conventional short putters.
To improve their putting some golfers are no longer using a conventional short putter, and are now using a long putter (FIG. 3) in a simple pendulum type putting action, or a belly putter, which is a mid-length putter which hinges from the belly button.
As such there are now three distinct types of putter: short, mid. (or belly), and long.
A long putter is between 120 and 130 cm. in total length, and has two grips, an upper grip 4, located at a top end of a first shaft 5, and a lower grip 6, below it on the shaft. The player grasps the upper grip 4 with one hand when putting the ball, and this upper hand is stabilised against the body, usually the chest (FIG. 4), or chin, and remains relatively stationary during the putting stroke. The other hand grips the lower grip 6, providing the force to hit the ball, and the putter is pivoted with this lower hand from a pivot point in the approximate area of the upper hand.
The long putter is sometimes difficult to transport as it is too long for many car trunks. Therefore it would be an advantage if a long putter was adjustable for length so the golfer could alter the length to shorten the putter for ease of transportation.
Also when using the long putter, (FIG. 4), the golfer draws attention to the use of this putter, as one elbow 7, sticks out. This ungainly looking method can cause the golfer embarrassment.
Putters may have the single short grip 1 (FIGS. 1 and 2), the pair of short grips 4, 6 (FIG. 3), or a single long grip 8, with various tapers (FIGS. 5 and 6), or no taper (FIG. 7).
In late 1999 a well known professional golfer called Paul Azinger began using a mid length putter which is long enough to fit into his belly button when assuming the normal putting posture. A belly putter has one or two grips. This method has become known as belly putting, and in the last two years has grown in popularity with four golfers in the top fifty of the world rankings now using a belly putter.
Belly putters are commercially available in various fixed lengths from 100 to 115 cm.
There is a link to companies selling belly putters on the web site http://www.bellyputter.com.
It would also be an advantage if a belly putter was adjustable for length, so the golfer could alter the length to suit their desired posture, and that this adjustment was conforming to the Rules of Golf, as determined by the United States Golf Association™, and the Royal and Ancient Golf Club of St Andrews™.
In 2000, Dave Pelz, a well respected golf instructor; and coach to many world ranking professionals, published a golf instructional book called “The Short Game Bible” (Broadway Books, New York, 2000). Mr Pelz noted that to avoid adopting a weak and unstable wrist position at the address position it is advisable to use a shorter putter than is currently available.
Short putters are commercially available only in various fixed lengths from 80 to 90 cm.
Therefore it would also be an advantage if a short putter was adjustable for length so the golfer could alter the length to suit their desired posture.
Telescoping golf shafts are described in patents, and the following patents represent the approaches to securing the shafts.
Middleton, U.S. Pat. No. 5,733,203, describes a telescoping putter, with two shafts, with a “locking screw” to secure the shaft.
Harrison, U.S. Pat. No. 5,649,870, describes a telescopic shaft arrangement where simple friction secures the two telescoping tapered shafts in a semi fixed position.
Mazzocco, U.S. Pat. No. 4,674,747 discloses a golf club having adjustable length shaft retractable between fully extended and collapsed positions. The golf club has plural concentric telescopic interlocking tubular sections which produce a friction lock between the tubular sections in a fully extended position There is a club commercially available utilizing this principle (http:/www.allinonegolfclub.com).
Sundin, U.S. Pat. No. 5,584,769, describes a shaft which can be constructed of two or more telescopically-adjustable or collapsible members to allow the same to adjust to different lengths for individual golfers. However, Sundin does not specify how the two shafts are to be secured in position.
Lee, U.S. Pat. No. 5,569,096, describes “the shaft inserted into the handle, threadably tightening a locking nut over a flexible ring and a external thread until the flexible ring is squeezed over the shaft prevents the shaft from slipping—thereby effectively locking the shaft in the desired length.”
Napolitano, U.S. Pat. No. 5,282,619, describes a shaft which has a number of telescopic sections where a locking nut and a compression ring permit adjacent sections of the telescopic section to be locked in a fixed position relative to each.
Whilst all the above patented inventions technically allow adjustment none are both variable in length and in accordance with the Rules of Golf.
The Rules of Golf do not allow readily made adjustment to clubs, and until May 2002 an adjustable length putter has never been determined as legal by the United States Golf Association.
18 pars Ltd, a company in which the applicant is a shareholder, is in receipt of a letter from the United States Golf Association™, which states “the default-locked mechanism submitted has been judged conforming with the Rules of Golf.” (letter from the United States Golf Association, April 2002, Decision 2002-185).
This is the first time ever that a length adjustable putter has been approved. The United States Golf Association™ has decided the default locked mechanism submitted can not be inadvertently, or secretly adjusted by the golfer during the play of a round of golf.
A mechanism which is conforming for belly putters is also likely to be judged conforming for regular shorter putters. Whilst not as critical as for belly putters, it is nevertheless advantageous to be able to customise the length for all types of putters, to suit the golfer's physique, and preferred posture when putting.